Telephone substation apparatus



May 15, 1951 J. M. HAYWARD ET AL 2,553,255

TELEPHONE SUBSTATIQN APPARATUS Filed Sept. 28, 1948 I s Sheets-Sheet 1 V J.M.HAVWARD l/V VENTORS QA. Jamvsom WRNE/SSER .4 TTORNEY May 15, 1951 J. M. HAYWARD ET AL TELEPHONE SUBSTATION APPARATUS 3 Sheets-Sheet 2 Filed Sept. 28, 1948 FIG. 4

FIG. 7

J. M. HAYWARD INVENTORS CIA. JOHNSON, JR.

By M. R. NEISSER ATTORNEV Patented May 15, 1951 UNITED STATES PATENT OFFICE 2,553,255 TELEPHONE SUBSTATION APPARATUS John M. Hayward, Summit, Charles A. Johnson, Jr., Murray Hill, and Wilson R. Neisser, East Orange, N. J assignors to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Application September 28, 1948, Serial No. 51,612

2 Claims. (Cl. 179-100) 1 This invention relates to telephone substation apparatus and more particularly to an apparatus unit for use in connection with a telephone substation set.

2 design, of a more permanent nature whereby to eliminate accidental and unplanned disturbance thereof by the installer or repairman.

In accordance with still another feature of the An object of the invention is to improve the 5 invention, means are provided whereby the exoperation of telephone substation apparatus and ternal conductors, as placed in position adjacent to substantially reduce the cost incident to the to the associated terminals during manufacture initial production of such apparatus. of the apparatus unit, are temporarily held in Telephone substation apparatus includes, in such positions until all the wires have been so addition to the elements familiar to all users, i.e. positioned. The entire wiring assembly may the transmitter, the receiver, the supporting then be simultaneously permanently connected means therefor and the bell or ringer, certain by a single mass soldering operation. other essential elements such as inductive coils, In accordance with yet another feature of the condensers, resistors and the like, the exact invention a novel terminal arrangement is procombination depending to some extent upon the vided for certain of the capacitors whereby the specific type of substation circuit involved. In terminal members serve not only as such but the past it has been the common practice to also as the mechanical supporting means for mount these less familiar elements, together with said capacitors. the ringer, in a separate box technically termed In accordance with another feature of the inthe subscriber set but commonly referred to as vention novel means are associated with one of the bell box. More recently, the practice has been successfully introduced of mounting these elements in the base of the telephone set itself thereby producing the type of substation instrument commonly referred to as a combined hand In accordance with a specific embodiment of telephone set. the present invention, certain of the essential The apparatus unit contemplated by the preselements of a subscribers telephone circuit, ent invention is applicable particularly to the which for the purpose of the present description combined type of telephone set although it is alone will be assumed to be of the general type also applicable to the older type wherein eledescribed in the copending application of Botsments are mounted separate from the telephone ford-Boyson-Aikens-Dietze-Goodale-Inglis, seinstrument itself. rial No. 793,170, filed December 22, 1947, entitled In accordance with a feature of the present Subscriber Telephone Set, are compactly invention a substantial portion of the elements grouped and mounted in a common metallic of a telephone substation installation, i. e. exhousing. The elements so grouped include the clusive of the familiar elements, are cominduction coil of the anti-sidetone circuit; the pactly grouped within a common container auto-transformer and associated resistor and cathereby resulting in manufacturing economy, a pacitor which comprise the balancing network; marked simplification of station set assembly the resistor and capacitor provided for suppresand W a d Ot e l OT advantages sion of dial interference; and an additional ca- W c l e ly pp fTOm the fOHOW- pacitor utilized in the transmission circuit. 111% dfiscrlptlon' In Particular, this? common A plate of suitable insulating material serves groupmg 9f elements: Prevlously Separately as a cover for the housing, as a mechanical suphouied and mounted permits 5 1 9 pottmg port from which the various elements are hung treament for an elements that a11.the for mechanical support, and as a terminal plate elements may be sub ected to the same apphcar ne m k ticn of a potting compound. 0 n 0 g 00 In accordance with a further feature of the The gr0up1r.1g these vanpus elements ma invention, a novel terminal arrangement is procommon housmg an essentlal p m h vided for the apparatus unit whereby connectemment of maxlmum compactness, results m tions that are apt to require changing from time manufacturing economy d greatly simplifies time t t subscriber-,5 premises a of a type and facilitates station assembly and wiring. The requiring only the use of a screw-driver tool, (no 00111111011 hOIlSing Serves as a constraining m a s soldering operation involved), while connections for the required moistureproofing compound, that are not apt to require changing are, by which may thus be applied to all the elements the inductive coils which serve not only as clamping means for the core laminations thereof but also as the mechanical supportingelement for the coil assembly.

as a unit, and, in addition, provides magnetic shielding whereby to prevent cross-talk.

A full understanding of the arrangements contemplated by the present invention and appreciation of the various desirable features thereof may be gained from consideration of the following detailed description and the attached drawings in which:

Fig. 1 is a plan view of the apparatus unit showing particularly the arrangement of the connecting block (cover), a portion of the housing wall being broken away to show one of the elements mounted therein;

Fig. 2 is a partial sectional view taken on line 2--2 of Fig. 1 showing the arrangement of one of the soldering terminals;

Fig. 3 is a sectional view similar to Fig. 2 but showing a modified form of soldering terminal;

Fig. 4 shows the cover with elements supported thereby, removed from the housing and inverted to better disclose the elements, a portion of the cover being broken away to show the manner of supporting the induction coil;

Fig. 5 is an end view in partial section showing particularly the core arrangement of the induction coi1 and the clamping and supporting means associated therewith;

Fig. 6 is a view in partial section showing particularly the coil and core arrangement of the auto-transformer and the capacitor supporting means associated therewith;

Fig. '7 is a view in partial section showing a modification of one of the capacitor supporting means shown in Fig. 4;

Fig. 8 shows a still further modification of the capacitor supporting means;

Fig. 9 is a schematic showing of the circuit arrangement of the elements of the apparatus unit; and

Fig. 10 is a schematic showing of the manner in which the apparatus unit is associated with other elements of a subscribers telephone set.

Referring now to the drawings, and first to Fig. 1, an apparatus unit of the general type contemplated by the present invention is illustrated comprising a bowl-like metallic housing I I provided with a cover l2 of suitable insulating material. plate or connecting block and, as shown, is provided with strategically located terminals. These terminals are both of the soldered type, as [3, l4 and i5 and of the screw type as l6, l1, 2| and 22. Certain of the terminals, as 23 and 24, provide for both solder and screw-type connections.

Cover I2 is held in position on the housing by suitable cars 25 and 26 which extend upward from the housing and project through suitable recesses or apertures in connecting block or cover l2 and are subsequently bent over to contact the upper surface of the cover. Housing H is provided with a suitable flange or mounting plate 21 to facilitate mounting.

In addition to the terminals mentioned, certain free terminals, as 3! and 32, are provided for convenient interconnection of other parts of the substation equipment.

It is contemplated that in certain instances, during manufacture and assembly of the apparatus unit, all of the external conductors or leads which are subsequently to be soldered to terminals of the connecting block may first be assembled adjacent to the respective terminals after which they may all be soldered permanently in place by a single simultaneous operation referred to as mass soldering. Obviously such a method,

Cover I2 serves also as a terminal if successfully practiced, offers many advantages from the standpoint of economical manufacture and, in order to render such a method feasible in the present instance, the novel method illustrated of temporarily holding the conductors in position has been provided.

As shown, opposed projecting members have been provided at strategic positions on the connecting block, the separation between the respective opposed members being exactly determined in accord with the diameter of the respective Wire or wires to be accommodated whereby the space provided in each instance is such that the respective wire or wires may be forced down between the opposed members and held thereby until the soldering operation has been completed. For example, wire 32 is held in soldering position by contact with the opposed surfaces of projections 43 and 46; wire 45 by members 56 and 41; wire 5| by members 52 and 53; wire 54 by members 55 and 56; and wire 57 by members II and 12. On occasion this same plan may be utilized to position the wires at points remote from the terminals. in order to provide a neater assembly and facilitate the wiring; for example, as illustrated, wires 55 and 57 are subjected to the additional positioning support of members 13 and M.

It will be understood that it is contemplated that wires of various diameters will be utilized in the assembly, the spacing of the respective members being exactly determined in each instance by the diameter and the number of the wires to be accommodated.

As shown particularly in Fig. 2, terminal l3, which is typical of both the solder and screw type terminals, is provided with wire and solder receiving aperture 15 and extension 16 which pro jects downwardly into the housing for a purpose described subsequently. The terminal is held in position in connecting block l2 by upsetting eyelet portions as illustrated. When this terminal is used for screw connections the aperture 15 is tapped to receive the terminal screw.

In certain instances trouble has been encountered through solder dropping down through the wire receivin aperture into the housing and causing electrical shorting of the elements there in. In order to forestall the possibility of such troublesome occurrence the novel type of terminal illustrated in Fig. 3 may be provided. In the instance of this modified terminal 11, it will be observed that aperture 18 is of substantially reduced size as compared to aperture 15 of terminal [3; the size of aperture 18, as a matter of fact, being such that it is substantially entirely closed by the wire positioned therein. The possibility of solder dropping through the aperture into the housing and causing damage is therefore eliminated.

In addition to the spaced projections on plate I2 referred to above, other projections are provided at strategic points for different purposes. For example certain of the projections, as 8| and 82, serve to prevent undesired lateral movement, beyond predetermined allowable narrow limits, of wire terminals or spade tips which may be con-- nected to the screw-type terminals on plate l2.

Referring now to Fig. 4, and considering firstinduction coil 83, which is also shown in part in similar end members 86 and 81 (Fig. 4) and 88 5. and 89 (Fig. 1) are provided. which serve, inconjunction with suitable bolts and nuts, as clamping means for the core laminations. Each of these members is provided with an extending tab on each end, the four upper extending tabs being adapted to pass through apertures in cover I2 and to be bent over whereby to mechanically hang induction coil 83 from cover I2 thereby providing its sole mechanical support. This turned-over or upset position of respective upper extensions IIII and IE2 of members 86 and 8'! is illustrated in Figs. 4 and 1 while the similar position of upper extensions I63 and I04 of members 88 and89 is shown in Fig. 1.

The downwardly extending portions of clamping members 86, 8'1, 88 and 89 are useful in po sitioning other elements of the assembly; for example extensions I65 and I06 (Fig. 5) of members 86 and 8'! serve to aid in positioning resistor III! while the downward extensions of members 38 and 89 (not illustrated) aid in the positioning of resistor III (Fig. 4).

Referring still to Fig. 4, and also to Fig. .6, autotransformer IIZ comprises a single-winding coil positioned on the upper leg of a cor which is made up of two groups of U-shaped magnetic laminations I I3 and I I4;' these two groups of laminations are assembled with a similarly shaped separator I I5 of insulating material positioned between the two groups whereby an elongated or lateral air-gap is provided. In view of the relatively large difference between the inner diameter of the coil and the size of the core leg a spacer II6 has been provided for maintaining the coil in stable position on the core leg. Spacer II6 may conveniently be in the form of a cellulose acetate sheet pleated and allowed to expand against the inner surface of the coil due to its natural resiliency.

Lamination groups H3 and H4 and spacer II5 are clamped in assembled position by the action of side plate [3| in conjunction with suitable bolts and nuts. As shown most clearly in Fig. 6 side member I3I is provided with angular ears I33 and I34 which engage the inner surface of cover plate I2. This permits the auto-transformer to be hung from the under side of the cover plate thereby providing the sole mechanical support therefor; suitable machine bolts I35 and [35 (Figs. 6, 4 and 1) are provided for attaching supporting ears I33 and I34 to cover I2.

As shown in both Figs. 4 and 6, side clamping member I31 is provided with a downwardly extending portion (i. e. downwardly with respect to the normal assembled condition of the unit as shown in Fig. l), which terminates in a U- shaped clamping member I31. This member I31 receives and securely holds in proper position capacitors MI and I42; suitable fiat or appropriate- 1:; formed sheets of insulating material may be provided, as illustrated, to separate the two capacitors from each other and from the surface of clamp I31.

It will be apparent from the above that there has been provided a novel unitary means which eificiently performs three important function in the assembly; namely provides clamping action for the core members, provides mounting means for the two capacitors, and provides means for supporting the entire assembly from the cover. This novel arrangement adds materially to the compactness and mechanical assembly of the apparatus unit contemplated by the invention.

Referring again to Fig. 4, capacitors I43 and I44, which are preferably of the metallized paper type, are bound together as a compactvv unit by insulating tape I45. The capacitors are preierably provided on each end with connecting means in the form o1 a schooped metallic de posit inv the general manner disclosed by Strab Patent 2,274,011 and Burn Patent 2,323,020. Thus capacitors. I43 and I44 are provided on one; end with conductive connecting portions I46 and I41. respectively, and. on the oppositev ends with similar' conductive, portions (not illustrated). In the present instance, advantage is taken of this construction whereby to provide, in a novel manner, a combined supporting and external connecting means for the two capacitors.

As shown in Fig. 4, terminals I5 and I6 (Fig. l) are. provided with respective downwardly extending portions I48 and I49 while terminalv 24 (Fig. 1) is provided with a similar extending portion IBI which is partially shown in Fig. 4. Extension I48 makes electrical contact with corn necting surface I49 of capacitor I43; extension I49 with connecting portion I41 of capacitor I44 and, in a similar manner, extension I6I makes electrical contact with the conducting surface (not shown) provided on the other end of capacitor I44. (These contacts are preferably made by soldering, the schooped coatings pro vided on the ends of the capacitors permitting such procedure.) of providing electrical connections, the ends of the extension portions are so spaced withv respect to the longer dimensions of the capacitors that the two capacitors", which are assembled as a unit by the tape I45, are held snugly between the terminal extensions which thereby serve the dual function of providing the necessary electrical connections to the capacitors and also the means for mechanically hanging thecapacitors from cover I2 thereby providing the sole mechanical support therefor.

If desired the modification illustrated in Fig. 7 may be provided in accordance with which a separate mechanical support, in the form of U- shaped bracket I62, is provided for the support of capacitors I43 and I44; in this instance the capacitors are snugly held by the bracket, suitable separators in the form of insulating sheets being Y mounting arrangement may be provided if desired by in effect extending the bracket I 31 of Fig. 6 so that it forms. a mounting. clip for capacitors I43 and I44. This mounting clip not only supports the associated capacitors, but by its, clamping action prevents loss of capacity due to swelling of the capacitors from the heat of the potting operation. The modified bracket I50 (Fig. 8 may be provided with an extension I5I arranged to rest against the under side of the cover plate I2 or in a socket provided therein, the purpose of this extension being to more positively position capacitors I52 and I53 (corresponding to capacitors M3 and I44 of Fig. 4) near the bottom of the housing I! 50 that the capacitors will be sure to be covered by an adequate thickness of the moisture excluding layer of potting compound.

While references have been made above to the use of bolts and nuts for holding various parts together, other suitable fastening devices such In addition to their function.

as tubular" or other rivets may be used if de=-" sired.

' A suitable aperture !54 (Fig-1) is provided in cover l2 through which, when all elementsare' in position, a potting compound may be poured. Slots in the upper edge of housing 1 I, as slots I55 and I56, provide space through which excess compound may drain off.

"A schematic showing of the circuit connections of the various items of the apparatus unit is provided (Fig. 9) in order to further describe the relationship of the various items. Reference may be had to the copending application of Botsford- Boyson-Aikens-Dietze-Goodale-Inglis referred to above for disclosure of the function of thevarious items in the over-all subscribers telephone cir-' cuit. It might be stated here merely that autotransformer H2, resistor Ill and capacitor l4! comprise the balancing network of the antisidetone subscribers circuit, resistor I01 and capacitor I42 provide for suppression of dial radio interference, induction coil 83 is a part of the anti-sidetone circuit, capacitor M3 is utilized in the transmission circuit, and capacitor 554 is'utilized in the signalling circuit.

It is contemplated that the apparatus unit will be mounted within the supporting housing of the subscribers telephone set, if it be of the com-- bined type, and it will be apparent that the novel unit offers important advantages, particularly from the standpoint of compactness and ease of a. manufacturing standpoint marked economies result from the grouping of the various elements a in one housing, testing is facilitated, and a common potting operation serves for all the collected items; the novel arrangement provided for temporarily holding the wires in positionon the cover renders mass soldering, with its attendant economies, feasible. The various novel waysin which elements such as clamping members have been designed to perform additional functions results not only in economic savings but also in the attainment of an unusually compact and mechanically efficient assembly. It will be apparent that installation of the unit is simplified by the arrangement of terminals provided and a particularly valuable feature resides in the manner in which the terminals have been divided into two groups, those likely to be changed from time to time at the subscribers station (screw type) and those of a permanent nature which should not ordinarily be changed by the installer (soldered type).- Use of the apparatus unit improves the operation of the subscribers telephone circuit 4 materially; an important contributing factor'to this improvement arises from the fact that the metallic housing provides magnetic shielding for theelements mounted therein and thereby prevents cross-talk.

It is of course of vital importance in the operation of a modern telephone system that, both for reasons of economic operation and of good pub-- lic relations, the substation equipment be as efficient and troublefree in its performance as p0ssible and that repair andrevisions, when neces sary, be" made as unobtrusively as possible. All

of these factors are materially furthered by use of the novel apparatus unit contemplated by the present invention. Fig. 10 shows in a schematic fashion, how call ing dial I'H may be added to a telephone subscribers set already installed. Dial I'll will usually require four leads, two of which will be attached to the apparatus unit of the present invention and two of which will be attached to element I12 which is not a part of the present invention but the function and arrangement of which will be clear from the copending application of Botsford-Boyson-Aikens-Dietze-Goodale- Inglis referred to above. Lead H3 from the handset switch (which for manual service is connected to terminal RR of the apparatus unit) is shifted to terminal F when the change to dial service is made. As shown, the dial leads to be attached to the apparatus unit incidental to the change to dial service and lead I13, the position of which on the terminal plate is to be changed, are provided with spade type terminals and the terminal arrangement of the apparatus unit is such that only a screw-driver operation is required for attachment of the dial. In the same manner, other connections that are likely to require changing While the set is installed on the subscribers premises are so arranged that only a screw-driver operation is required, thus elimihating the objectionable use of a soldering operation on the premises. nections not likely to be changed are of the soldered type in order to eliminate accidental and unintended disturbance by the installer.

Whfle specific embodiments of the invention have been selected for detailed description the invention is not intended to be restricted in its application to such embodiments. The embodiments described should be looked upon as illustrative of the invention rather than as restrictive thereof.

What is claimed is:

1. A telephone substation apparatus unit com prising a metallic housing, a cover plate of inpairs of projections being adjacent to one of said termmal members, each projection of a respective pair being so positioned With respect to the other projection. of the pair and with respect to the diameter of the wire to be attached to the associated terminal member that the space between the two projections is slightly less than the diameter of said wire.

2. In a telephone substation unit comprising a housing, a cover of insulating material for said housing, a plurality of circuit component supports on the undersurface of said cover, and a p1u-- rality of circuit components secured to said supports, the improvement which comprises a plurality of terminals on the upper surface of said covenmeans connecting said components to said terminals, a plurality of exterior leads to said terminal interconnecting said components and a plurality of pairs of spaced projections on said On the other hand, concover adjacent certain of said terminals the projections of each pair being so positioned with respect to each other that the space between the two projections is Substantially the same but slighly less than the diameter of the lead to an associated terminal member.

JOHN M. HAYWARD.

CHARLES A. JOHNSON, JR.

WILSON R. NEISSER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,122,290 Mack et a1 Dec. 29, 1914 Number Number 15 834,981 

